US3813489A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low light television camera
Assignee: International Standard Electric Corp
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Filing: 1972-11-03
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Granted: 1974-05-28
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Expires: 1992-11-03
Abstract
Abstract The phosphor screen of an image intensifier fiber-optically coupled to the target of a television camera tube is connected to a point in the video amplifier which provides a signal to decouple the target from ground. The phosphor acts as a guard ring to avoid capacitive effects. The feedback signal from the amplifier is equal in magnitude and phase to the voltage signal produced at the target. An added guard ring may be connected to the same potential as the phosphor.
Inventors
- 👤 M Bedgood
- 👤 M Ramsay
- 👤 W Barnes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:46
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/08; H01J31/26; H01J31/28; H01J31/34; H01J31/38; H01J31/36; H04; H04N; H04N23/00; H04N23/40
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
96 words
A low light level television camera system comprising a video amplifier, a television camera tube having a photoconductive target at one end connected to provide an output voltage signal to said video amplifier, an image intensifier tube having an output phosphor screen, and fiber optic means coupling said phosphor screen to said target, said phosphor screen being connected to a point in said video amplifier providing a feedback voltage signal equal in magnitude and phase to said output voltage signal from said target and being at a predetermined direct voltage with respect to a reference potential.
Claim 2
Dependent Claim
96 words
A low light level television camera system comprising a video amplifier, a television camera tube having a photoconductive target at one end connected to provide an output voltage signal to said video amplifier, an image intensifier tube having an output phosphor screen, and fiber optic means coupling said phosphor screen to said target, said phosphor screen being connected to a point in said video amplifier providing a feedback voltage signal equal in magnitude and phase to said output voltage signal from said target and being at a predetermined direct voltage with respect to a reference potential.
Claim 3
Dependent Claim
67 words
The television camera system of claim 1 wherein a guard ring is disposed around said camera tube adjacent said target and is connected to said point in said video amplifier providing said feedback voltage signal equal in magnitude and phase to said output voltage signal from said target, and said image intensifier output phosphor screen is at a fixed potential with respect to said camera tube target.
Claim 4
Dependent Claim
23 words
A television camera as claimed in claim 2 wherein said phosphor screen and guard ring are connected together at a common direct voltage.
References Cited (Backward Citations)
US3341655A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-27 | 1977-11-26 | 1978-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-27 | 1981-11-26 | 1982-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-27 | 1985-11-26 | 1986-05-28 | $7700.00 | Window Closed / Lapsed |